2.3

• The SA:V ratio (Surface Area to Volume Ratio) determines the efficiency of the cell.
• Smaller cells typically have a higher SA:V ratio and are more efficient in material exchange.
• Moving materials in and out of cells becomes more difficult as the cell size increases.
• Smaller cells allow for more efficient exchange of materials with the environment.
• Surface area (SA) is the amount of surface covering the outer part of the cell.
• Larger cells struggle to meet the demand for internal resources and waste removal due to a decrease in relative SA as volume increases.
• The surface area of the plasma membrane must be large enough to adequately exchange materials
• Membrane folding increases surface area.
• As organisms increase in size, the surface area to volume ratio decreases, affecting properties like heat exchange rate with the environment.
• Loss of folding in cells can lead to decreased efficiency in nutrient absorption.
• Cells and organisms use specialized exchange surfaces, such as stomatal openings in leaves, to obtain and release molecules from the surrounding environment.
• The small intestine has folded structures called villi, which greatly increase its surface area.
• Elephants have large, flat ears that allow for increased thermal energy dissipation.
• More folds result in more surface area.